2-Chloro-1-methylpyridinium iodide. A suitable reagent for peptide synthesis

2-Chloro-1-methylpyridinium iodide is a coupling reagent for peptide synthesis. By its use different peptides were synthesized with protected di- and trifunctional amino acids. While urethan-protected amino acids react free of racemization, the fragment condensation needs N-Hydroxysuccinimide, as shown by the Young test.     

Development of a novel mammalian display system for selection of antibodies against membrane proteins

Reliable, specific polyclonal and monoclonal antibodies are important tools in research and medicine. However, the discovery of antibodies against their targets in their native forms is difficult. Here, we present a novel method for discovery of antibodies against membrane proteins in their native configuration in mammalian cells. The method involves the co-expression of an antibody library in a population of mammalian cells that express the target polypeptide within a natural membrane environment on the cell surface. Cells that secrete a single-chain fragment variable (scFv) that binds to the target membrane protein thereby become self-labeled, enabling enrichment and isolation by magnetic sorting and FRET-based flow sorting. Library sizes of up to 10⁹ variants can be screened, thus allowing campaigns of naïve scFv libraries to be selected against membrane protein antigens in a Chinese hamster ovary cell system. We validate this method by screening a synthetic naïve human scFv library against Chinese hamster ovary cells expressing the oncogenic target epithelial cell adhesion molecule and identify a panel of three novel binders to this membrane protein, one with a dissociation constant (K_D) as low as 0.8 nm. We further demonstrate that the identified antibodies have utility for killing epithelial cell adhesion molecule–positive cells when used as a targeting domain on chimeric antigen receptor T cells. Thus, we provide a new tool for identifying novel antibodies that act against membrane proteins, which could catalyze the discovery of new candidates for antibody-based therapies.     

Community structure of the deep sea fishes in the northern Gulf of Aqaba,Red Sea (Osteichthyes and Chondrichthyes)

The aim of this study was to investigate the community structure of deep sea fishes in the northern Gulf of Aqaba. Deep fish traps, short lines and long lines were deployed at depth ranges from 60 to 700 m between June 2014 and May 2015. A total of 369 fish individuals belonging to 37 species in 21 families were collected. The most abundant family observed in deep fish traps and short line was the commercially important family Sparidae, whereas the most abundant family in long line catch was the commercially unimportant fish family Muraenidae. The most abundant fish species sampled by deep fish traps and shortline was Blueskin Seabream, Polysteganus coeruleopunctatus. The most abundant species in long line catch White-spotted Moray, Gymnothorax johnsoni. In fish traps and with short line, the most commonly caught species was Blueskin Seabream. White-spotted Moray was the most common long line catch. Depth distribution for 37 deep fish species and GIS maps for the two main commercial fish species Blueskin Seabream and Bigeye Hound Shark, Iago omanensis were documented.     

Osmotic stress due to changes in plasma glucose and its regulation in IDDM patients.

Intravenous glucose tolerance tests (30 g, 5 min, constant rate) were performed in 8 IDDM patients and in 8 controls. The consequences of the osmotic pressure, induced by glucose, were investigated. Serum choline esterase was used as an endogenous marker of serum dilution. Five minutes after the end of infusion plasma glucose was raised by 182 +/- 12 mg.dl-1 in patients and by 189 +/- 6 mg.dl-1 in controls. Choline esterase values decreased by 6.6 +/- 0.8% and 6.3 +/- 1.0% respectively, P less than 0.01 each. Calculated water shifts into the extracellular space were 924 +/- 112 ml and 882 +/- 140 ml respectively. Fifteen minutes after the end of infusion glucose decreased by 32 +/- 1 mg.dl-1 in IDDM patients and by 57 +/- 2 mg-1 in controls. Serum choline esterase recovered by 2.6 +/- 0.2% and 2.7 +/- 0.2% respectively, P less than 0.01 each, indicating comparable water correction in spite of the slower fall of glucose in IDDM patients. Water correction was more rapid than glucose fall. Diuresis (46 +/- 4 ml versus 42 +/- 3 ml) or cellular uptake of serum solutes (electrolytes, amino acids, urea, creatinine) could not explain this. It is hypothesized that accumulation of free intracellular glucose reduces the osmotic gradient and facilitates cellular water re-uptake.     

Role and implications of nanodiagnostics in the changing trends of clinical diagnosis

Nanodiagnostics is the term used for the application of nanobiotechnology in molecular diagnosis, which is important for developing personalized cancer therapy. It is usually based on pharmacogenetics, pharmacogenomics, and pharmacoproteomic information but also takes into consideration environmental factors that influence response to therapy. Nanotechnology in medicine involves applications of nanoparticles currently under development, as well as longer range research that involves the use of manufactured nano-robots to make repairs at the cellular level. Nanodiagnostic technologies are also being used to refine the discovery of biomarkers, as nanoparticles offer advantages of high volume/surface ratio and multifunctionality. Biomarkers are important basic components of personalized medicine and are applicable to the management of cancer as well. The field of nano diagnostics raises certain ethical concerns related with the testing of blood. With advances in diagnostic technologies, doctors will be able to give patients complete health checks quickly and routinely. If any medication is required this will be tailored specifically to the individual based on their genetic makeup, thus preventing unwanted side-effects.     

Design,synthesis and anticancer activity of novel pyrimidine and pyrimidine-thiadiazole hybrid glycosides

Abstract

New 1,3,4-thiadiazole thioglycosides linked to substituted pyrimidines were synthesized via glycosylation of 1,3,4-thiadiazole thiol compounds. Also, novel 1,2,3-triazole derivatives linked to carbohydrate units were prepared using the standard click chemistry conditions employing the Cu(I)-catalyzed azide-alkyne cycloaddition of substituted-aryl-azides with a selection of alkyne-functionalized sugars. The chemical structures of the new derivatives were verified using various spectroscopic techniques, such as IR, ¹H NMR, ¹³C NMR and elemental analyses. The cytotoxic activities of the prepared compounds were investigated in vitro against human liver cancer (HepG-2) and human breast adenocarcinoma (MCF7) cell lines. In addition, the biological evaluation of the new compounds involved the investigation of their effects on a human normal retinal pigmented epithelial cell line (RPE1) using the MTT assay.